


Kaitlyn Stark: An Avengers Story

by Batgirl713



Category: Captain America (Movies), Iron Man (Movies), The Avengers (Marvel Movies), Thor (Movies)
Genre: Bruce Is a Good Bro, F/M, Loki Posing as Odin, Loki is a good guy, Original Character Insert, Peggy Carter Feels, Sam Wilson is a flirt, Steve Rogers Can Not See A Good Thing, Steve Rogers is clueless, Tony Stark Is a Good Bro, Tony Stark is Overprotective
Language: English
Status: In-Progress
Published: 2018-08-20
Updated: 2018-12-16
Packaged: 2019-06-30 00:33:08
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 4
Words: 7,956
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/15740472
Author URL: https://archiveofourown.org/users/Batgirl713/pseuds/Batgirl713
Summary: Kaitlyn Stark, Tony Stark's younger sister, has been told stories of Captain America from her father and her Aunt Peggy since before she can remember.  What happens when she meets the man she's heard about non stop growing up.  What happens when they start to become close friends and avenge the world together?  One thing is certain Tony Stark is not happy.





	1. In the Beginning

**Author's Note:**

> This is the first story I've ever published on here. I hope you like it. I tried to stick to the MCU timeline as best I could so bear with me. Also, any helpful comments would be appreciated. Thanks for reading I hope you enjoy reading it as much as I had writing it. :)

"Peggy, I need to talk to you." Howard says on the end of Peggy Carter's phone.

"What have you gotten yourself into this time, Howard? You're not selling weapons to the enemy again are you?"

"First of all, you know I never did that. Second of all, very funny. Now, will you just meet me for lunch this week?" Peggy thinks for a moment then finally agrees.

"The L&l Automat, Monday at 12 o'clock."

"It's a date.  See you then, Peg."  Peggy hangs up the phone and writes  **Howard at 12** **pm** on her table calendar by the phone when her husband, Brian calls from the bedroom.

"Who was that on the phone, dear?"

"Just Howard.  He wants me to meet him for lunch.  He said he needs to talk to me."

"Well, just remind him you're a happily married woman and I'm not too inclined on sharing."

"Darling, Howard's married."

"That didn't mean a whole lot to him before."

"Brian, you're being ridiculous."

"That's my job dear, being your ridiculous husband, which I'm going to be late for if I leave now."  She pecks him on the cheek before he leaves for the night shift at the police department.  He grabs his lunchbox and heads out the door.

On Monday Peggy gets to the diner around 11:45 and finds a spot in the middle of the diner.  Howard walks in 15 minutes late finds Peggy and heads toward their table.  She gets up to hug him, they sit down in the old beat up booth, a waitress stops to take their order then leaves giving Peggy and Howard time to talk.

"How have you been, Peg?"

"Good, how are you doing?" 

"I'm doing better than these seats.  When did they get so raggedy?"

"And Maria?" Peggy says changing the subject.  "How is married life for you two?"

"Well, that's what I wanted to talk to you about." 

"Howard you better no-"

"Maria's pregnant."

"Oh Howard that's wonderful!"

"I'm gonna be a dad.  Can you believe that?"

"Honestly with they way you got around I'm  surprised it didn't happen sooner."  Howard chooses to ignore this and continue taking.

"And I want you to be my kids' godmother.  We, Maria and I want you to be our kids' godmother.  Well, what do you say?"

"Of course, I will Howard, I would be honored!"

Six months go by and Anthony Edward Stark comes into the world.  From day one Tony is glued to his Aunt Peggy's side.  She's there for all the major events in Tony's life from his first tooth to his first science fair project.  Then in 1982 Tony gained a sister, Kaitlyn Marie Stark, and Peggy gained a goddaughter.  Unfortunately with Howard's alcoholism and his constant screaming matches with Tony, Tony became more and more distant until on Kaitlyn's fifth birthday Tony left to attend MIT.  Tony leaving left a hole in Kaitlyn, she was very close to her brother and she didn't know what to do or how to process him leaving for school.  Trying to lift her spirits Peggy taught Kaitlyn hand to hand combat, how to defend herself should the need arise when she got older. 

"Just because you're a woman doesn't mean you are weak.  You are as powerful as any man out there.  Never forget your worth my darling girl."  Peggy told her. 

Tony graduated two years later, but following in his father's footsteps started living a reckless bachelor lifestyle.  By the time he was 21 he already had 2 DUI's and totaled several of Howard's cars.  Every time he got off with a warning, the perks of being Howard Stark's son.  The morning or December 16th, 1991 Kaitlyn like many children in America planted herself in front of the T.V. in the middle of the living room watching 'Darkwing Duck' and eating a bowl of Cocoa Pebbles.  Tony, passed out on the couch from the party he attended last night, stirs as cartoon duck's theme song plays from across the room.

"Could you turn that down a bit?  I'm nursing a hangover over here."

"You wouldn't have that problem if you didn't go out drinking all night."

"Hey!"  Tony shoots up into a sitting position.  "What I do is none of your business."  Tony falls back to his previous position on the couch.  A minute or two passes and tony begins to yell at Kaitlyn.

"Can you turn that shit down!"

"I don't need this.  I'm eating breakfast in the kitchen." Kaitlyn leaves the living room heading for the kitchen not turning the T.V. off in the living room out of spite.  Tony angrily gets up off the couch to turn the T.V. off.  He turns around heading back plopping on the couch promptly falling back to sleep.  He's awoken several hours later to the sound of his mother's piano playing and singing voice.

"Try to remember the kind of September when grass was green."  She stops singing noticing that her son has woken up but she continues playing the piano.  Wake up, dear, and say goodbye to your father." Howard moves the blanket off Tony's face.

"Who's the homeless person on the couch?" he says.  Tony chuckles as he gets up off the couch, faces his father while wearing a Santa hat.  A souvenir he no doubt got from last nights party.

"This is why I love coming home for Christmas, right before you leave town."

"Be nice, dear," Maria says to her husband, "he's been studying abroad."  Howard wastes no time to make a comment.

"Really?  Which broad?  What's her name?"

"Candace." Tony replies.  Howard takes the Santa hat off Tony's head and tosses it on the couch.

"Do me a favor?  Try not to burn the house down before Monday."

"Oh?  So it's Monday?  That is good to know, I will plan my toga party accordingly.  Where are you going?" Tony asks his mom.

"Your father's flying us to the Bahama's for a little getaway."  Howard goes to speak.

"We might have to make a quick stop-"

"At the Pentagon.  Right?" Tony interrupts his father and continues talking to his mom.  " Don't worry you're going to love the holiday menu at the commissary."

"You know they say sarcasm is a metric for potential.  If that's true you're going to be a great man someday.  Be nice to your sister.  It's the holidays, you haven't seen each other for months, there is no reason you two should be fighting already.  I'll get the bags."  Howard walks out of the room, Maria tries to calm her son who is clearly upset by his fathers comments.

"He does miss you when you're not here."

"Yeah? Well he's got a funny way of showing it."

"He just wants to see you reach your full potential."  Howard walks into the room carrying suitcases on either side of him.

"Maria, are you ready?"

"Yes, dear." She turns to Tony.  "Your sister is in school until Wednesday.  Pick her up, will you?  Behave and don't torment each other, understand?"

"Yes, mom."  She pecks him on the cheek. 

"I love you, Tony."

"Bye, mom."

Howard and Maria Stark walk out the front door of the house to their car, not knowing it will be for the last time.  Not knowing that they will never make it to the Pentagon.  Not knowing that they will never see their kids again.  Tony does as he is told and picks up is sister from school  shortly after his parents leave for their trip.  Kaitlyn climbs into the front seat of Tony's sports car, eyes looking down the whole time.

"How was school today?" Tony asks trying to make up for acting like a dick this morning.

"Fine."

"Just fine?"

""Just leave me alone, Tony.  I just want to go home."

"If this is about this morning I'm sorry.  I shouldn't have yelled at you."

"It's not about that can we please just go home?"

"Okay. Heading home."

Tony starts driving home but the silence is too much for him to handle so he tries to attempt conversation again.

"Just so you know mom and dad left for their trip so we have the whole place to ourselves until Monday." Silence.  "You know what that means?"  More silence.  "Oh come on, Kait, play along."  Even more silence.  "It means I'm in charge and anything goes!"  Tony looks over at Kaitlyn whose expression hasn't changed since Tony picked her up from school.  Tony decides to bring out the big guns.  "And if anything goes that means pizza and ice cream for dinner with ice cream being served first and pizza being optional of course.  I even got your favorite."  Kaitlyn starts to perk up at this.

"Chocolate and mint chocolate chip so you can swirl them together."

"You betcha, but you gotta promise me you're going to stop being such a sourpuss.  You've only got two more days of school left this week then it's Christmas break.  so turn that frown upside down."

"I knew it was too good to be true.  But your terms and conditions seem possible so I suppose I can accept them as long as you keep your end of the deal I'll keep mine."

"You drive a hard bargain but it is a pleasure doing business with you."

"Tony, can we build a fort and watch a movie like we used to?"

"Sure, what do you want to watch?  Pick a movie, any movie?"

"Any movie?"

"Your choice, pick whatever you like."

"The Great Mouse Detective."

"Except that."

Tony."

"I'm just pulling your leg now go inside and get started on that fort.  I'll be inside in a minute."

Kaitlyn races into the house as Tony parks his car in the garage.  Once inside the house Tony bumps into Kaitlyn who has already grabbed several pillows and blankets not caring to take off her backpack first.  Tony laughs at her as all the pillows topple to the ground leaving her small arms.

"Don't laugh at me."

"I'm not laughing at you, Kait.  I'm laughing with you.  You might want to take off your backpack first.  Your equilibrium may be off with that heavy thing and all the pillows.  I'm going to order pizza and we'll get this party started."

"Okay, Tony." Tony orders pizza and he and Kaitlyn pig out while watching Kaitlyn's movie selection in Kaitlyn's own man made pillow fort.  By the end of the movie both Tony and Kaitlyn are passed out from their sugar high.  Only static was on the T.V. screen when Tony awoke to someone pounding on the front door.  Half awake Tony carefully lays a pillow under Kaitlyn's head, replacing his lap.  Tony sleepily drags himself to the front door rubbing his eyes to wake himself up for whoever is at the front door.  Tony opens the door to see Peggy Carter standing on the front step.  Tony has no idea why his fathers long time friend is standing on the porch step in front of him.

"Peggy, what are you doing here?"

"Oh, Tony.  I'm -.  May I come in."  Tony can see she's been crying, why he doesn't know.

"Yeah, Kaitlyn's asleep.  Let's go into the kitchen."  They make their way into the kitchen tiptoeing their way there so as not to wake Kaitlyn.  Tony searches for a dim light to turn on so he and Peggy can see each other.  He finds the light and looks at Peggy, he notices she's started crying again.

"Peggy are you alright?  What's wrong?"

"Tony, I'm very sorry to have to tell you this but I couldn't have the-, that is I thought it might be better coming from a friend than from an official."

"Peg, what are you talking about?  Tell me what?"  Peggy takes a deep breathe, takes Tony's hand in hers and gathers up the strength to tell him why she's in his kitchen tonight.

"Tony, your parents were in a car accident this evening."

"What?  Are they okay.  Where are they?  What happened?"

"Darling, they- they didn't make it.  They passed away.  I'm so sorry, dear.  If you need anything I'll be around.  If you need help with Kait-" Tony's mind started to go blank as he started to process what his godmother just told him.  Then they both heard a shuffling of feet.

"Aunt Peggy.  Why are you crying?"  Kaitlyn stood in the doorway of the kitchen holding her blanket and her favorite stuffed bear.

"Come here, sweet girl.  I need a hug."  Kaitlyn walks towards her, Peggy picks her up and gives her a big hug.

"Did something bad happen?"

"Yes."  Tony answered her.  "I don't want you to worry about it right now, okay?  All you need to know right now is that everything is going to be okay.  Okay?"

"Okay."

"Kaitlyn, I love you."

"I love you too, Tony."  Kaitlyn gets down from Peggy's lap and heads back to the living room into the pillow fort.  Tony and Peggy stay up for a bit after that.  Peggy clears her schedule to help Tony make arrangements for everything.

"I'll be back around 9.  Are you going to tell her what happened?"

"Yeah.  I just don't know how to tell her."

"You'll figure it out.  If you need me just call and I'll be here faster than you can say God save the queen."

"Thanks, Peg."  He walks her out to her car.  Once she's safely made it to the end of the driveway and out of sight Tony goes back inside to check on Kaitlyn who is fast asleep in the living room in her pillow fort.  He falls asleep next to her holding on to her for dear life, which is how Peggy found them the next morning.


	2. The Avengers Initiative

Eighteen years later Tony and Kaitlyn are all grown up and running the family business...well, sort of. At the ripe age of 26 Kaitlyn had been working for her brother for 4 years as a PR agent for Stark Industries. At this time Tony had also been kidnapped by terrorists in Afghanistan who had been hired to kill him by family friend and fellow business partner, Obediah Stane. Once Tony became Iron Man he immediately grabbed the attention of a secret spy organization by the name of SHEILD who kept frequent tabs on him. One agent in particular, Agent Phil Coulson would show up tonight and ask for Tony's help.

"You're good on this end. The rest is up to you." Tony says as he flies up and away from the Atlantic ocean heading back towards New York City. Kaitlyn comes up in his helmet speaking on the other end of the line.

"You disconnected the transition lines? We're off the grid?"

"Stark Tower i about to become a beacon of self sustaining clean energy." Tony replies. Pepper comes up over Tony's helmet monitor as well.

"Wow. So maybe our reactor takes over and it actually works?"

"I assume." Tony and Kaitlyn say at the same time.

"Light her up." With Tony's command floor by floor the Stark Tower's lights turn on till finally reaching the STARK on top.

"How does it look?" both women ask him.

"Like Christmas but with more me."

"You mean more us. That's my name up there too you know." Kaitlyn reminds him. "We have to go wider on the public awareness campaign."

"You two need to do some press. I can do some more tomorrow. I'm working on the zoning on the next billboards." Pepper is cut off.

"Pepper," Tony chimes in, "you're killing me. Remember? Enjoy the moment."

"Then get in here and I will."

"Ugh, come on you guys you could at least wait until I get out of the room."

"Think of it as a five minute head start." Tony lands on the balcony of Stark Tower as his suit comes off piece by piece with the aide of his new tech.

"Sir, Agent Coulson of SHIELD is on the line." JARVIS comes over Tony's ear piece.

"I'm not in. I'm actually out."

"Sir, I'm afraid he's insisting." JARVIS reports.

"Close the line JARVIS. I got a date." Tony strides into his new penthouse. Across the room he sees the love of his life Pepper with his little sister Kaitlyn both gazing at the monitors for the arc reactor energy cell in front of them.

"Levels are holding steady... I think." Kaitlyn said uncertain.

"Of course they are, I was directly involved. And I thought you were leaving."

"Yeah, yeah. Let me grab my things and I'll get out of your hair so you can enjoy your new penthouse."

"Yours is right below us." Tony smirked.

"No thank you.  I'll just go out and get some Chinese and wait for you guys to fall asleep."  Kaitlyn starts to gather up her things all scattered around the penthouse.

"Suit yourself."  Tony turns to Pepper.

"How does it feel to be a genius?"

"Well, I wouldn't know now would I?" Kaitlyn rolls her eyes at Pepper's response.

"What do you mean? All of this came from you."

"No all of this came from that." Pepper taps a finger on the arc reactor embedded in Tony's chest.

"Give yourself some credit, please, Stark Tower is your baby. Give yourself twelve percent of the credit."

"Twelve percent!?"

"An argument could be made for fifteen."

"Oh you did not just say that!  You are in trouble, Tony." Tony looks at her.

"What?"

"Twelve percent for my baby?" Pepper starts laughing at the ridiculousness of the conversation.

"Well, I did do the heavy lifting. Literally, I lifted the heavy things. And sorry, but the security snafu? That was on you." Kaitlyn heads towards the elevator trying to get out of this mess while she can still leave unscathed.

"My private elevator..."

"You mean  _our_ elevator?" Pepper cuts him off.

"...was teeming with sweaty workman. I'm going to pay for that comment about percentages in some subtle way later, aren't I?"

"I don't think she's gonna be that subtle." Pepper chuckles at Kaitlyn's comment and pours herself and Tony a glass of champagne.

"Weren't you supposed to be leaving?"

"I'm trying the doors won't open.  Trust me I don't want to be here any more than you want me here."

"Which I don't.  It's an elevator you have to push the button."

"I pushed the button. I am pushing the button."Kaitlyn starts pushing the elevator button multiple times to prove a point.

"Sir," JARVIS' voice comes over Tony's phone "the telephone. I'm afraid my protocols are being overwritten." Just then JARVIS' voice fades out and Agent Phil Coulson comes over Tony's phone.

"Stark we need to talk." Kaitlyn turns to see what Tony is going to do. He picks up his phone and speaking to it he says:

"You have reached the life model decoy of Tony Stark. Please leave a message." Both women try to silence their laughter but noise still escapes them both.

"This is urgent."

"Then leave it urgently." The elevator door open to reveal Agent Coulson who hangs up his phone upon arrival."Security breach."

"Phil." Kaitlyn greets him.

"That's on you." Tony says to Pepper.

"Come in." Pepper ignores Tony.

"I can't stay." he says right away.

"Come on in we were celebrating."she says.

"They were celebrating." Kaitlyn signals over to her brother and Pepper.

"Which is why he can't stay." Tony says with a smile.

"We need you to look this over as soon as possible." Coulson extends the file he's carrying out to Tony.

"I don't like being handed things."

"That's alright," Kaitlyn pipes up, "because I love to be handed things." Kaitlyn takes the file from Coulson and hands it to Tony in his free hand taking the champagne flute from his other hand and handing it to Coulson.

"Official consulting hours are from eight to five every other Thursday."

"This isn't a consultation."

"Is this about the Avengers." Kaitlyn says quickly and Phil gives her a disapproving look and she takes it back. "Which I know nothing about."

"The Avengers Initiative was scrapped, I thought. And I didn't even qualify." Tony walks away with Coulson's files in hand.

"I didn't know that either." She says unconvincingly.

"Yeah," Tony continues. "Apparently I'm volatile, self-obsessed, don't play well with others."

"That, I did know."

"This isn't about personality profiles anymore." 

"Whatever, Kaitlyn, Miss Potts, got a minute?" Kaitlyn and Pepper walk over to Tony who has set the file onto his own desk to be downloaded onto his databases.

"You know," Tony said to Pepper, "I thought we were having a moment."

"I was having twelve percent of a moment."

"Told ya." Tony glares at Kaitlyn for a second then brings his attention back to the files in front of him.

"This seems serious, Phil seems pretty shaken." Pepper whispers to Tony.

"How did you notice? Why is he Phil?"

"Tony." Kaitlyn brings Tony back to the task at hand. "What is all of this." Tony looks at her then the monitors.

"This is uh, this." He takes his fingers and in a swift diagonal motion the files burst into multiple screens showing profiles on Captain America, Thor, Hulk, Hawkeye, Black Widow, and Loki with the tesseract which draws Tony, Pepper, and Kaitlyn's attention the most.

"I'm going to take the jet to DC tonight." Pepper says.

"Tomorrow." Tony insists.

"You have homework. You have a lot of homework."

"Well what if I didn't."

"If you didn't?"

"Yeah."

"You mean if you finished?" Tony nods his head yes and Pepper leans in to whisper something in his ear which makes Kaitlyn roll her eyes and Agent Coulson look away in embarrassment.

"Square deal fly safe." Pepper walks towards Coulson and the both exit to the elevator.

"Do you want to fuel up now or later?" Kaitlyn asks as Tony picks up the tesseract hologram to inspect it.

"I should be alright." He says inspecting the hologram.

"Are you sure? I'm going to order Chinese. It could be hours before we get everything done." Tony stops what he is doing and looks at his sister.

"What do you mean 'we'?"

"You're going to need some help on this one. There is a lot of information to comb through in as little time as possible."

"I've had shorter deadlines that weren't this dangerous. Now go home, Kait."

"No."

"Excuse me?"

"You heard me. I said no. Whether you think it or not you could use my help. I already could write the biography on Steve Rogers from memory and I spent more time with Natatsha than you did ogling her. Admit it I could be an asset of information."

"It's too dangerous."

"I can protect myself. Aunt Peggy taught me how to fight remember? Besides, I'm more of a behind the screen guy. Everybody needs a behind the screen guy. I'm yours."

"JARVIS is my behind the screen guy. You are my sister. I'm not gonna watch you get hurt."

"I'm not going to get hurt. I'm just offering my research skills, which you could use. That's it. First sign of danger and I'm outta here. Okay?" Tony looks at the ground thinking for what feels like forever. He knows she's not going to stop hounding him. He finally agrees to letting her help him because face it she is right, she can help him and there's no one else he'd rather work with than his little sister.

"Okay fine, but as soon as there is any sign of danger you are gone, running in the opposite direction. You hear me?"

"Loud and clear."

"And don't be making goo goo eyes at Rogers."

"Me? I would never."

They work late into the night and early into the next morning.  Kaitlyn and Tony both have done nothing but stared at screens taking in as much information as possible.

"Okay, I'm done I can't take this anymore.  I need a break or my brain will explode and my eyes will bulge out.  I don't know how you can do this all the time.  I need coffee.  You need coffee? I'm gonna get coffee."

"Kait!." She looks at Tony.

"You need to sleep."

"I'm fine.  I just need to take a second.  I'm almost done with the extraction theory papers."

"Seriously, go take a nap.  You've helped enough."

"Tony-"

"It's ok.  Catch a few z's."

"Tony-"

"Rest up.  You're gonna need your energy if-"

"Tony!  Your phone.  It's Coulson."  Tony picks up his phone and speaks with Agent Coulson briefly.  Tony hangs up and starts gathering all the files together.

"What's going on?"

"Timeline's been moved up."

"What?  To when?"

"Now." Tony backs everything up on a thumb drive and puts it safely in his pocket.  Kaitlyn stares at him, watching his every move.

"You're coming aren't you?"  Kaitlyn looks puzzled.

"I thought you didn't want me anywhere near the danger."

"I don't.  That's why I'm dropping you off at the Helicarrier."

"Then, where are you going?"

"Stuttgart, Germany."


	3. Only Here To Find The Cube

**Summary for the Chapter:**

> Kaitlyn finally gets to meet Captain Rogers, is protective over Dr. Banner, and Tony enjoys embarrassing his sister.

Tony drops Kaitlyn off at the Helicarrier where Agent Coulson meets her outside.  
"He won't like this." Coulson says  
"Tell Fury to get over it." Tony looks at Kaitlyn. "Remember-"  
"I know. Any sign of danger run in the opposite direction. Just be safe ok?"  
"You got it. See you on the flip side, kid." Tony blasts off headed towards Germany to join Captain America and Agent Romanoff.  
"Kaitlyn, come meet Dr. Banner. He's already started working on finding the cube."  
"How far has he gotten?"  
"Not sure. He arrived about an hour before you did."  
"That's plenty of time to get up and running."  
"Miss Stark, I have to warn you-" Kaitlyn cuts him off.  
"Phil, I've seen everyone's files. I know what I'm getting myself into. If SHIELD thought Dr. Banner was a possible threat there is no way you'd give him free rein on a ship like this let alone a lab where he could do as he pleases." She raises an eyebrow at Coulson.  
"Just don't upset him in anyway. Play it safe."  
"Don't make him angry? Yeah, I think I could manage that for you." Kaitlyn laughs a little to herself and Coulson smiles as he escorts her into the wishbone lab where Dr. Banner is working. Coulson and Kaitlyn enter the lab which startles Dr. Banner and Kaitlyn immediately apologizes.  
"Sorry, we didn't mean to startle you."  
" It's alright." the Dr. says. "I'm fine."  
"Dr. Banner this is-"  
"Kaitlyn Stark, Tony Stark's younger sister. It's a pleasure to meet you. I've read so much about you." Kaitlyn extends her hand to him which he shyly shakes and nervously looks to the ground.  
"I'm sorry. I don't know anything about you other than you're rich and your brother is Iron Man."  
"He's the face of the company. I just make sure he looks good." she smiles. Bruce tries to let go and smile at her but he doesn't know this woman and he's not too quick to let people in.  
"So what are you doing here? You don't have any special powers."  
"Neither does Tony."  
“I just mean, um.” Bruce is struggling to find his words before Kaitlyn can start on him.  
“I know what you mean. Look I’m here just like you. To help find the cube. Last time I checked you didn’t need your powers for that.” Kaitlyn stares at Bruce until she gets an answer.  
“You’re right. I don’t need my- the other guy to help find the cube. And you’re okay working with a guy like me?” Bruce looks at the floor again.  
“Dr. Banner, I would be honored to work with you.” Kaitlyn gives him a smile. Bruce can tell Kaitlyn is genuinely being honest and he fills her in on his progress. They work for a few more hours when Coulson drops by to let them know they’ve captured Loki and Iron Man, Agent Romanoff, and Captain America are headed back toward the base. Shortly after, they learn that the three have encountered, Thor, Loki’s Asgardian brother who is traveling with the three do gooders to assist in stopping Loki’s plans.  
Once Agent Romanoff lands the Quinjet on the Helicarrier armed troops escort Loki inside and down the hall right outside the wishbone lab where Kaitlyn and Bruce are working. Loki looks through the window and smiles at Bruce as he continues striding down the hall. Bruce takes off his glasses and rubs his temples as if the look caused him pain. Kaitlyn notices this and immediately comes to his aide.  
“Hey,” she says “are you okay? He didn’t hurt you, did he?” she looks behind her out the window where Loki once was trying to figure out if he could do something like that. Hurt people without even touching them or being in the same room as them. Bruce collects himself, Places his glasses back on the bridge of his nose and looks at her.”  
“I’m fine. I don’t know what just happened. Really, I’m okay.” He goes back over to what he was working on and Kaitlyn just stares at him with a ‘tell me the truth look’ on her face.  
“Really, I’m fine.” There’s a moment of silence then Bruce decides to change the subject. “Have you met Captain Rogers, yet? You can go fawn all over him if you want. I’m good here by myself for a minute or two.” Kaitlyn giggles at his comment.  
“I don’t fawn over people, Dr. Banner.”  
“Please, Miss Stark, just call me Bruce. We don’t need the formalities.”  
“Then don’t call me Miss Stark.” she retorts back.  
“Shouldn’t you go check on Tony? Make sure he’s okay and all.”  
“He’s a big boy who can take care of himself.” She continues working on a separate computer, both of them refusing to leave the lab until Coulson comes in to request their presence with Director Fury, Captain America, Tony, Thor, and Agent Romanoff. They reach the conference table, Agent Romanoff and Captain Rogers are already sitting there focused on Fury and Loki with Thor off to the side listening to their conversation intently. Kaitlyn and Bruce listen to the conversation between Fury and Loki.  
“In case it’s unclear,” Fury starts, “you try to escape, you so much as scratch that glass.” Fury pushes a button on an electrical panel, mere feet from the cylindrical cell entrapping Loki, that makes the floor beneath it drops away to nothing.  
“Thirty thousand feet straight down in a steel trap. You get how that works?” Fury pushes another button and restores the floor beneath Loki’s cell again. Fury gestures to Loki and then the panel again.  
“Ant. Boot.”  
“It’s an impressive cage. Not built, I think, for me.” Loki says with a chuckle.  
“Built for something a lot stronger than you.” Fury responds.  
“Oh I’ve heard.” Loki looks into a camera like he knows Bruce is watching. Loki is looking directly at Bruce through the screen Bruce, Natasha, Kaitlyn, and Captain Rogers are watching. Kaitlyn watches Bruce ready at any moment to lend a comforting hand.  
“A mindless beast makes play he’s still a man. How desperate are you, that you call on such lost creatures to defend you?”  
“How desperate am I?” Fury asks as he moves slowly towards the cage. “You threaten my world with war, you steal a force you can’t hope to control, you talk about peace and you kill ‘cause it’s fun. You have made me very desperate. You might not be glad that you did.”  
“Oh it burns you to have come so close, to have the Tesseract, to have power, unlimited power, and for what?” Loki smiles and looks at the camera once more. “Warm light for all mankind to share?” Loki then faces Fury again, done toying with Bruce’s mind for now. “And then to be reminded what real power is.” Fury smiles at his comment.  
“Well, let me know if ‘real power’ wants a magazine or something.” Fury walks away from Loki trapped in his glass cage. The monitors on the conference table turn off and Captain Rogers looks up for the first time since Kaitlyn first saw him sitting at the conference table. All she can think about is how happy Aunt Peggy will be to learn that Steve is alive and how handsome he is, just like Peggy told her. Bruce is the first to break the silence.  
“He really grows on you doesn’t he?” Kaitlyn smiles at Bruce’s comment.  
“Loki’s gonna drag this out. So, Thor what’s his play?” Steve asks.  
“He has an army called the Chitauri. They’re not of Asgard nor any world known. He means to lead them against your people. They will win him the Earth, in return, I suspect, for the Tesseract.” Thor explains.  
“An army, from outer space?” Steve asks befuddled.  
“So, he’s building another portal.” Kaitlyn’s trying to piece everything together then she comes to a solution. “That’s what he needs Erik Selvig for.”  
“Selvig?” Thor turns around at Erik’s name.  
“He’s an astrophysicist.” Bruce explains.  
“He’s a friend.” Thor responds.  
“He has them under some kind of spell. Along with one of ours.” Natasha informs the group.  
“I wanna know why Loki let us take him. He’s not leading an army from here.”  
“I don’t think we should be focusing on Loki. That guy’s brain is full of cats, you can smell crazy on him.”  
“Have care how you speak. Loki is beyond reason but he is of Asgard, and he is my brother.”  
“He killed eighty people in two days.” Natasha reminds him.  
“He’s adopted?” Thor tries to justify his defense for Loki.  
“I think it’s the mechanics.” Bruce gets them back on track with the task at hand. “Iridium, what do they need the Iridium for?”  
“It’s a stabilizing agent.” Kaitlyn and Tony say at the same time. Kaitlyn looks behind her and there’s Tony walking in with Coulson.  
“I’m saying, take a weekend; I’ll fly you to Portland. Keep love alive.” Coulson starts heading in a different direction and Tony goes over to Thor.  
“Means the portal won’t collapse on itself like it did at SHIELD. No hard feelings point break, you got a mean swing.” Kaitlyn gets up from her seat next to Bruce to head over to Tony.  
“What do you mean by mean swing, Tony?”  
“It’s nothing. We’re all here. We’re all fine.” He leans down to whisper in her ear. “You start the show?”  
“Of course, Tony.” Tony continues talking to the group, ignoring Kaitlyn.  
“Also, means the portal can open as wide and stay open as long as Loki wants.” Tony looks around. “Ah, raise the mizzen mast, ship the topsails.” Everyone including SHIELD personnel look at him strangely, Kaitlyn hides her face in her hands. “That man is playing Galaga! Thought we wouldn’t notice, but we did.” Tony covers one of his eyes and looks around the command area of the ship. “How does Fury even see these?” He asks Agent Maria Hill.  
“He turns.” she replies sternly.  
“Sounds exhausting. The rest of the raw materials, Agent Barton can get his hands on pretty easily.” Kaitlyn cuts him off.  
“Only major component he still needs is a power source of high energy density.”  
“Something to kick start the cube.”  
“When did you guys become experts in thermonuclear astrophysics?” Agent Hill asks the two Starks.  
“Last night.” they reply.  
“The packet?”  
“Selvig’s notes?”  
“The extraction theory papers. Are we the only ones who did the reading?” Kaitlyn asks Tony.  
“Does Loki need any particular kind of power source?” Steve asks.  
“He’d have to heat the cube to a hundred and twenty million kelvin just to break through the Coulomb barrier.” Bruce informs them.  
“Unless,” Kaitlyn starts, “Selvig has figured out how to stabilize the Quantum Tunneling effect.”  
“Well, if he could do that he could achieve heavy-ion fusion at any reactor on the planet.”  
“Finally.” Tony exclaims. “Someone who speaks English.” Steve looks around at everyone else.  
“Is that what just happened?”  
“Tony, this is Dr. Banner, obviously.” Kaitlyn introduces them. Tony holds out his hand to shake Bruce’s.  
“It’s good to meet you, Dr. Banner. Your work on anti-electronic collisions is unparalleled. And I’m a huge fan of the way lose control and turn into an enormous green rage monster.”  
“Tony.” Kaitlyn scolds. Bruce puts up a hand to say it’s okay.  
“Thanks.” Bruce tells Tony and Fury enters in behind them.  
“Doctor Banner is only here to track the cube. I was hoping you might join him.” He says to Tony.  
“I’d start with that stick of his. It may be magical but it works an awful lot like a HYDRA weapon.”  
“I don’t know about that.” Fury says. “But it is powered by the cube. And I’d like to know how Loki used it to turn two of the sharpest men I know into his personal flying monkeys.”  
“Monkeys? I do not understand-” Steve cuts Thor off.  
“I do!” The room goes completely silent, everyone stares at Steve.  
“I, I understood that reference.”  
“Shall we play, Doctor?”  
“This way, sir.”  
“Tony you have some catching up to do.”  
“I look forward to it. I expect you took good notes.”  
“Naturally.”  
“Hey, Stark.” Fury yells across the room and both Tony and Kaitlyn turn around.  
“Miss Stark.” Fury clarifies. “May I have a word?” She looks back at Tony and Bruce.  
“I know where it is. I’ll catch up with you in a minute. It’ll be okay.” Kaitlyn heads over to Fury.  
“Miss Stark.”  
“Director Fury.”  
“Let me make it perfectly clear you are also only here to assist in tracking the cube.  
“Yes, sir.”  
“And the next time you disobey orders I won’t be so lenient. Do I make myself clear?”  
“As crystal, sir.”  
“Good.” Fury walks away from Kaitlyn. Kaitlyn lets out a sigh of relief that that was all she had to endure. She turns around to head back to the lab and immediately runs into Captain Rogers.  
“I’m sorry. I didn’t think you were gonna turn around that fast. Are you okay? I know Fury can be a little tough.”  
“Oh, that?” Kaitlyn lets out a little laugh. “That’s just Nick. He doesn’t, that is, he- I did break the rules, you know. I’m not really even supposed to be here or know about any of this stuff. Um, anyway. I don’t think we’ve met properly. I’m Kaitlyn Stark.” She holds out her hand to shake his.  
“Steve Rogers, ma’am.” Kaitlyn blushes at his old fashioned manners.  
“I, I know. That is, you worked with my father during the war. Howard Stark. Tony’s my brother.” She continues to shake his hand.  
“Yes, that’s right. I was very sorry to hear about what happened to your parents. Howard was an amazing man.”  
“Thank you. I was nine when they passed away so I don’t remember a lot about either of them.” Tony appears at the top of the stairs to see Kaitlyn shaking Steve’s hand.  
“Kait! Are you gonna come help or get lost in Rogers eyes all day!” Kaitlyn immediately pulls her hand away from Steve and her face flushes so red she could be the Red Skull himself.  
“Oh my god, I’m so sorry. I have to go.”  
“That’s okay. I’ll see you around Miss Stark.”  
“Please, call me Kaitlyn, or Kait.”  
“Alright. See you around, Kait.” Kaitlyn starts almost jogging away from Steve and up the stairs. When she reaches the top she punches Tony in the shoulder who laughs at her embarrassment all the way to the wishbone lab to meet back up with Bruce.


	4. Not of Use

**Summary for the Chapter:**

> Sorry this is a short one. Kaitlyn, Tony, and Bruce in the lab. Eventually Steve too.

Tony and Kaitlyn enter the wishbone lab where Bruce Banner is already working on locating the cube.  Kaitlyn looks mortified and all of the blood has rushed to her face. And then there’s Tony who can’t stop laughing.

“What did I miss?” Bruce asks them.

“Nothing!  Let’s just get back to work.”  Kaitlyn starts working on the computer tucked away in the corner as Tony fills Bruce in on what happened downstairs between Kaitlyn and Captain Rogers.

“Kaitlyn, I thought you didn’t fawn over anyone.”

“This wasn’t fawning Bruce, this was straight up flirting.  Which I told you not to do.” Tony explained.

“No, you told me not to make goo goo eyes at him.” She reminded him.  “And I was simply introducing myself after I sort of crashed into him, which was entirely his fault.  Now, can we please do what we came here to do and track the cube. Bruce have you gotten anything off the scepter?”  Banner has been scanning Loki’s scepter and finally comes up with some readings.

“The Gamma readings are definitely consistent with Selvig’s reports on the Tesseract.  But it’s gonna take weeks to process.”

“And we don’t have weeks.”  Kaitlyn notices Tony messing with another screen.  “Tony, what are you doing?”

“If we bypass their mainframe and direct route to the Homer cluster we can clock this at around six hundred teraflops.”

“And all I packed was a toothbrush.”  Kaitlyn grins and Tony chuckles at Bruce’s Comment.

“You know you should come by Stark Tower some time.  You’d love it, it’s candy land.”

“Thanks, but last time I was in New York I...kind of...broke Harlem.”

“Well,” Kaitlyn pipes up.  “I promise a stress free environment.”

“No tension, no surprises.” Tony zaps Bruce in the side.

“Ow.”

“Tony.”  Kaitlyn scolds him.  “I supposed with him around I can’t make any promises.  Steve enter the lab after seeing Tony poke the bear or Hulk as it were.

“Hey.”  Tony ignores Steve as he looks at Banner’s face.

“Nothing?”

“Are you nuts?” Steve asks Tony.

“Jury’s out!”  He says to Steve and brings his attention back to Bruce.  “You really have got a lid on it, haven’t you? What’s your secret?  Mellow jazz, bongo drums, huge bag of weed?”

“Is everything a joke to you?”

“Funny things are.”

“Threatening the safety of everyone on this ship isn’t funny.  No offense, Doc.”

“No it’s alright.  I wouldn’t have come aboard if I couldn’t handle pointy things.”

“You’re tip-toeing, big man.”  Tony says to Bruce. “You need to strut.”

“And you need to focus on the problem, Mister Stark.”

“Steve, you think we’re not?”  Kaitlyn still pink in the face asks him.

“Why did Fury call us in?  Why now, why not before? What isn’t he telling us?  I can’t do the equation unless I have all the variables.”

“You think Fury’s hiding something?”

“He’s a spy, Steve.  He’s the spy. His secrets have secrets.”  Kaitlyn comments from across the room.

“It’s bugging him too, isn’t it?” Tony gestures to Bruce as he pulls out a bag of blueberries and starts munching on his snack.  Steve looks at him.

“Uh, ahh, I just want to finish my work here and-”

“Doctor?” Steve asks him.

“‘A warm light for all mankind,’ Loki’s jab at Fury about the cube.”

“I heard it.”

“Well,” Bruce continues, “I think that was meant for you.”  Bruce gestures to Tony who offers him a blueberry. “Even if Barton didn’t tell Loki about the tower, it was still all over the news.”

“The Stark Tower?” Steve asks.  “That big ugly-”

“Hey, watch it.” Kaitlyn tells him and Tony gives him a look.

“Building in New York?”  Steve finishes.

“It’s powered by an arc reactor?  Self-sustaining energy source. That building will run itself for, what, a year?”

“It’s just the prototype.”  Tony answers between snacking.

“We’re kind of the only name in clean energy right now.”  Kaitlyn informs Steve. “That’s what he’s getting at.”

“So, why didn’t SHIELD bring them in on the Tesseract project?  What are they even doing in the energy business in the first place?”

“I should probably look into that as soon as my decryption program finishes breaking into all of SHIELD’s secure files.” Tony says nonchalantly.

“I’m sorry did you say-”

“JARVIS has been running it since Kait hit the bridge.  Thanks for that by the way.” He says to his sister.”

“Anytime, Tony.”

“In a few hours I’ll know every dirty secret SHIELD has ever tried to hide.  Blueberry?” He offers the bag to Steve.

“Yet you’re confused about why they didn’t want you around.” 

“An intelligence organization the fears intelligence?”

“Historically, not awesome.”  Kaitlyn answers her brother’s question.

“I think Loki is trying to wind us up.  This is a man who means to start a war and if we don’t stay focused he’ll succeed.  We have orders, we should follow them.” Kaitlyn, her face less pink rolls her eyes at Steve’s comment.  She knows that’s who he is, but hearing it out loud and while she was trying to work was slightly annoying.

“Following’s not really my style.”

“And you’re all about style, aren’t you?” Steve glares at Tony.

“Out of the people in this room, which one is ‘A’ wearing a spangly outfit and ‘B’ not of use.”

“Wow, thanks, Tony.”  Kaitlyn says from her corner across the room still working vigorously typing on the computer in front of her.

“Steve,” Bruce gets his attention, “tell me none of this smells a little funky to you?”

“Just find the cube.”  Steve turns around and exits the lab.  Kaitlyn watches him as he leaves. She notices him stop and turn to go in the opposite direction he was originally heading.

“That’s the guy my dad never shut up about?  Wondering if they shouldn’t have kept him on ice.”

“Guy’s not wrong about Loki, he does have the jump on us.  I’m gonna take a break, get some coffee. Rest my eyes from all the screen time.  I’ll be back in fifteen minutes.” Kaitlyn gets up from her spot in the corner, exits the lab and starts heading in the direction after Steve.

“What he’s got,” Tony brings back the conversation to Bruce, “is an ACME dynamite kit.  It’s gonna blow up in his face, and I’m gonna be there when it does.”

“I’ll read all about it.”

“Mhm, or you’ll be suiting up with the rest of us.”

“Now, you see I don’t get a suit of armor.  I’m exposed, like a nerve, it’s a nightmare.”  Bruce continues working trying to get past this part of their conversation.

“You know, I’ve got a cluster of shrapnel, trying every second to crawl its way into my heart. This,” he taps his arc reactor in his chest, “stops it.  This little circle of light. It’s part of me now, not just armor. It’s a terrible privilege.”

“But you can control.”  Bruce throws it back to Tony.

“Because I learned how.”

“It’s different.”  Bruce shrugs this off.

Tony swipes the screen between them that Bruce was working on forcing him to look at Tony.

“Hey, I read all about your accident.  That much Gamma exposure- should’ve killed you.”

“So you’re saying that the Hulk- the Other Guy- saved my life?  That’s nice. That’s a nice sentiment. Saved it for what?”

“I guess we’ll find out.”

“You may not enjoy that.”

“And you just might.”  Tony thinks for a moment.  “How long does it take to get a cup of coffee in this joint?”

“You think she got lost?”

“Quite the opposite.  I think she knows exactly where she is going.”

“It’s nice.”  Bruce starts working again.

“What is?”

“That you both care so much about each other.”

“I just don’t want her to get hurt.  I don’t know if you were paying attention but we do have a mass murderer from a different world on this carrier.”

“Crawling with trained SHIELD agents.”

“That’s what I’m afraid of.”  Tony gives Bruce a look. Meanwhile, Kaitlyn is following Steve’s every move through the carrier.  


End file.
